/Engine/Plugins/Online/OnlineServices/Source/OnlineServicesCommon/Public/Online/LobbiesCommonTypes.h
Todo: put this somewhere else.
namespace UE { namespace Online { template<typename AwaitedType> [TFuture](API\Runtime\Core\Async\TFuture)< [TArray](API\Runtime\Core\Containers\TArray)< AwaitedType > > UE::Online::WhenAll ( [TArray](API\Runtime\Core\Containers\TArray)< [TFuture](API\Runtime\Core\Async\TFuture)< AwaitedType >> && Futures ) } }